Which was meant to be the slower light beam in the Michelson Morley experiment? (1 Viewer)

[science]

Hey guys,

As in title. Was the one going perpendicular to the aethar wind, or the one going directly with and then directly against meant to be slower?

Cheers

Rory

 

[Rhinoz8142]

Doesn't matter, the point is that when the apparatus was rotated, there should have been a shift in the interference pattern if the aether wind did indeed exist

Do we call it aether or aether wind..

and OP, it dosent really matter

 

[anomalousdecay]

I think the light ray travelling directly with/against the flow of the aether should be the expected ray to be delayed a bit, causing the change in interference patterns.

Reason why is that it has to travel at a slower rate in theory if and only if the aether existed, when you look at the derivation.

However, the main focus here is the interference pattern produced. When rotated, if the interference patterns are different in comparison, then one light is arriving at a later time than the other. However if they are the same patterns both times exactly (after and before rotating 90 degrees), then what we can deduce is that both beams are travelling the same distance relative to before and after (NOTE: NOT relative to each other as beams, but relative to the cases before and after) regardless of the existence of an aether. Hence, this explains why light does not require a medium to propagate within. This deems the existence of the aether void and of no point now.

 

[Fizzy_Cyst]

As above, focus on the CHANGE in interference pattern which was expected when the device was rotated.

Here is a cool flashlet to allow you to visualise the motion of the beams as they split into perpendicular components.

http://galileoandeinstein.physics.virginia.edu/more_stuff/flashlets/mmexpt6.htm

 

[Thank_You]

What anomalousdecay said, as easy as that.

The light beam that travelled in the same direction as the aether and opposite direction when coming back

 

[tyrone97]

If you do the math it works out that the beam going parallel to the velocity relative to the aether should take a longer time to reach the detection device than the one going perpendicular (. However, as harrypotterfan said, the scientists conducting the experiment had no way to tell whether that the light beams were actually aligned with the velocity of Earth relative to aether - all they knew was that because of the "aether wind" the interference pattern should shift as the apparatus is rotated 90 degrees. Check Jacaranda Physics just to be sure. Also at Zohair97: "aether wind" refers to the wind-like effect of moving relative to the Aether, which causes the light to slow down/speed up relative to an observer on earth, and "aether" just refers to the hypothetical medium itself. Hope this helps.